Angela Merkel at the fourth summit on the war in Syria | TIME ONLINE

A major four-man summit in Istanbul on Saturday announced advice on the future of the country's civil war Syria advices. Turkish President Recep Tayyip Erdoğan, French President Emmanuel Macron, Kremlin leader Vladimir Putin and German Chancellor Angela Merkel will meet in the city of Bosphorus. United Nations mediator Staffan de Mistura will brief the four politicians on the situation in Syria.

The four countries specifically want to talk about the situation in Idlib northwest of Syria. The city is still in rebel hands. Russia as an ally of the Syrian government and Turkey as supporters of the rebels have created a demilitarized buffer zone. They want to prevent a government offensive.

The summit will also aim to relaunch the stalemate in the political process. All previous peace talks led by the UN have failed. In addition, a constitutional committee composed of representatives of the government and the opposition, decided last January, has not yet been formed.

This constitutional committee constitutes a serious challenge in the opinion of the outgoing UN Special Envoy of Mistura. The diplomat told the UN Security Council at a meeting after the end of his trip to Syria. De Mistura is currently working on the committee's launch before leaving office at the end of November.

The 71-year-old had announced a week and a half ago that it was surprising to leave his post for personal reasons. For more than four years, he had unsuccessfully tried to resolve the bloody conflict through negotiation.

The committee should include representatives of the Syrian government of President Bashar al-Assad, the opposition and neutral groups. However, the Syrian government on Wednesday called the constitution "sovereignty", saying that the issues would be settled by the Syrians alone and without foreign interference.

The chief negotiator of the main alliance of the Syrian opposition believes in peace in Syria only after the resignation of Assad. "It is impossible that a person who destroyed Syria and who is responsible for the death of many Syrians remains," said Friday in Moscow Nasr al-Hariri. According to Hariri, the Syrian government is hindering the formation of the constitutional commission.